JP2013072463A - Bearing device for wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device for a wheel, in which sealability can be enhanced by reducing the approach of foreign matter to a sliding contact surface of a lip of a sealing device.SOLUTION: A synthetic resin dam member 9 oppositely arranged to a flange side surface 3f, is provided on a flange side end surface 2d being an end surface on the wheel mounting flange part 3c side of an outer ring 2. The dam member 9 has a base part 91 adhered to the flange side end surface 2d and a projection part 92 projecting in a large number of cilium shapes from the base part 91, and the tip of the projection part 92 and the flange side surface 3f form a light contact or labyrinth clearance S.

Description

  The present invention relates to a wheel bearing device used in a vehicle such as an automobile.

Wheel bearing devices for attaching tire wheels and brake disks are used in vehicles such as automobiles. The wheel bearing device includes an outer ring fixed to the vehicle body side, an inner ring arranged concentrically with the outer ring and provided with a wheel mounting flange, and a rolling element interposed between the outer ring and the inner ring. And a sealing device for sealing the bearing internal space.
Since the wheel bearing device is used in a bad environment affected by rainwater or muddy water containing snow melting agent (hereinafter collectively referred to as “foreign matter”), the sealing device improves the sealing performance. For this purpose, the cored bar is fitted and fixed to the outer ring, and an elastic member is vulcanized and bonded to the cored bar to form a plurality of lips that are in sliding contact with the inner ring.

  In recent years, there has been a demand for lower torque in a wheel bearing device because of the need for improving the fuel consumption of vehicles, and the lip slides against the inner ring with a small contact pressure, so-called light contact. And in order to improve the sealing performance of the sealing device that slides in light contact, the sealing device further forms a labyrinth gap between the flange and the outer ring end surface, so that the foreign matter approaches the sliding surface of the lip. Is reduced. (Patent Document 1)

JP 2006-200628 A

  However, the above-mentioned wheel bearing device, particularly in a sports type vehicle, cools the brake disc by providing a large cooling hole in the dust cover of the wheel in order to improve the cooling performance of the brake attached to the flange. As a result, the usage environment becomes severe, and foreign matter may approach the sliding surface of the lip and enter the bearing. Therefore, the wheel bearing device has been challenged to reduce the approach of foreign matter to the sliding contact surface of the lip of the sealing device and to improve the sealing performance.

  The present invention has been made to solve such a problem, and provides a wheel bearing device capable of reducing the approach of foreign matter to the sliding contact surface of the lip of the sealing device and improving the sealing performance. The purpose is to do.

In order to solve the above-mentioned problem, the structural feature of the wheel bearing device according to claim 1 is that an outer ring member that is non-rotatably attached to the vehicle body side, and that the outer ring member rotates about an axis through a rolling element. An inner ring member that is supported, and a flange is formed at one end of the inner ring member in the axial direction so as to project outward in the radial direction and attach a wheel. A seal member that is fitted to an end portion of the inner peripheral surface and seals a bearing internal space between the outer ring member and the inner ring member; and the seal member is formed of an elastic member and is continuous with a side surface of the flange. In a wheel bearing device having an annular lip in sliding contact,
A flange side end surface that is an end surface on the flange side of the outer ring member is provided with a synthetic resin weir member disposed to face the side surface of the flange,
The weir member has a base bonded to the flange-side end surface, and a plurality of protrusions protruding in a ciliary shape from the base, and the tip of the protrusion and the side surface of the flange are light contact or labyrinth gaps Is to form.

  According to the wheel bearing device of the first aspect, the base portion is bonded to the flange-side end surface of the outer ring member, and the weir member having the protrusion portions protruding in a plurality of cilia shapes from the base portion is provided. Since a light contact or a labyrinth gap is formed with the side surface, the approach of foreign matter to the sliding contact surface of the lip can be reduced and the sealing performance can be improved.

  The wheel bearing device according to claim 2 is characterized in that the weir member is formed over the entire circumference of the flange-side end surface.

  According to the wheel bearing device of the second aspect, since the dam member is formed over the entire circumference of the flange side end surface, it is possible to reliably reduce the approach of foreign matter to the sliding contact surface of the lip and further improve the sealing performance. it can.

  A structural feature of the wheel bearing device according to claim 3 is that the protrusions are formed densely.

  According to the wheel bearing device of the third aspect, since the projections are formed densely, the approach of foreign matter to the sliding contact surface of the lip can be greatly reduced, and the sealing performance can be greatly enhanced.

  A structural feature of the wheel bearing device according to claim 4 is that the projection is roughly formed below the shaft center with respect to the upper side.

  According to the wheel bearing device of the fourth aspect, since the projecting portion is roughly formed below the shaft center with respect to the upper portion, foreign matter that has entered between the lip and the weir member can be discharged to the outside, The approach of foreign matter to the sliding surface can be reliably reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the proximity | contact of the foreign material to the slidable contact surface of the lip | lip of a sealing device can be reduced, and the wheel bearing apparatus which can improve sealing performance can be provided.

It is sectional drawing of the axial direction of the wheel bearing apparatus which is one Embodiment of this invention. (A) is the A section enlarged view of FIG. 1, (b) is the B section enlarged view of FIG. It is a perspective view of the dam member of the wheel bearing apparatus which is one Embodiment of this invention.

DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment in which a rolling bearing of the present invention is embodied will be described with reference to the drawings.
FIG. 1 is a sectional view in the axial direction of a wheel bearing device 1 according to an embodiment of the present invention. This will be described with reference to FIG. In the following description, the vehicle inner side indicates the left side in FIG. 1, and the vehicle outer side indicates the right side in FIG.

  The wheel bearing device 1 is, for example, for a front wheel of a front wheel drive vehicle (for a drive shaft), and has a double-row outward angular ball bearing structure. Specifically, the wheel bearing device 1 includes an outer ring 2 (outer ring member) fixed to the knuckle 20 on the vehicle body side, and a tire wheel on the axle side (not shown) arranged coaxially with the central axis 01 of the outer ring 2. ) And the inner shaft 4 (inner ring member) fixed to the brake disc rotor 30 and the inner ring 4 (inner ring member) fitted to the outer peripheral surface of the fitting portion 3a formed integrally with the inner end of the inner shaft 3 on the vehicle inner side. And a double row of balls 5 arranged in the circumferential direction between the outer ring 2 and the inner shaft 3 and the inner ring 4.

  On the inner peripheral surface of the outer ring 2, a raceway surface 2a for balls 5 arranged on the vehicle inner side and a raceway surface 2b for balls 5 arranged on the vehicle outer side are formed. A vehicle body mounting flange portion 2 c is formed on the outer peripheral surface of the outer ring 2 so as to protrude in the radial direction.

  A raceway surface 3b facing the raceway surface 2b of the outer ring 2 is formed on the outer peripheral surface of the inner shaft 3, and a wheel mounting flange portion is formed to project radially outwardly further to the vehicle outer side than the raceway surface 3b. 3c is formed.

  The inner ring 4 is press-fitted into the fitting portion 3a and integrated with the fitting portion 3a. On the outer peripheral surface of the inner ring 4, a raceway surface 4 a that faces the raceway surface 2 a of the outer ring 2 is formed.

  Between the outer ring 2 and the inner shaft 3 and the inner ring 4, a bearing inner space 6 for arranging balls 5 as rolling elements is formed, and this bearing inner space 6 is an elastic member on the vehicle outer side. The annular seal member 7 is sealed on the vehicle inner side by an annular seal member 8 made of an elastic member while allowing relative rotation of the outer ring 2, the inner shaft 3, and the inner ring 4.

  On the vehicle outer side, the weir member 9 is bonded and fixed to the end of the outer ring 2 on the side of the wheel mounting flange 3c facing the wheel mounting flange 3c.

  2A is an enlarged view of part A in FIG. 1, and FIG. 2B is an enlarged view of part B in FIG.

  The seal member 7 includes an annular cored bar 71 and an annular seal 72 (seal member).

  The metal core 71 is formed by bending a metal plate, and includes a cylindrical portion 71a and a circular plate portion 71b extending radially inward from the end of the cylindrical portion 71a. The outer peripheral surface of the cylindrical portion 71a is fitted and fixed by press-fitting to an end portion on the wheel mounting flange portion 3c side of the inner peripheral surface of the outer ring 2 on the raceway surface side. As a material of the core bar 71, for example, SPCC of a cold rolled steel sheet is used.

  The seal 72 is an elastic member made of rubber or the like, and includes a fitting portion 72a, a seal base portion 72b, and a lip portion 72c (lip), and is integrally fixed to the cored bar 71. The fitting portion 72a is formed at the end of the cylindrical portion 71a on the wheel mounting flange portion 3c side with a predetermined allowance between the outer ring 2 and the cylindrical portion 71a together with the inner circumference of the outer ring 2 on the raceway surface side. It is fitted and fixed to the surface by press fitting. The seal base portion 72b extends from the fitting portion 72a along the disc portion 71b toward the outer circumference of the inner shaft 3 on the raceway surface side. The lip portion 72c extends from the seal base portion 72b toward the outer periphery of the inner shaft 3 on the raceway surface side, and includes an axial lip 72d (lip) and radial lips 72e and 72f (lip).

  The axial lip 72d extends from the seal base portion 72b to the axial wheel mounting flange portion 3c side and the radial outer ring 2 side (radially outward side). The tip of the axial lip 72b is in sliding contact with the flange side surface 3f of the vehicle inner side surface of the wheel mounting flange portion 3c over the entire circumference.

  The radial lip 72e is positioned outward in the axial direction from the radial lip 72f. The radial lips 72e and 72f extend radially inward from the seal base 72b, and are in sliding contact with the outer circumference of the inner shaft 3 over the entire circumference.

  The weir member 9 is made of a synthetic resin and is made of an elastic member. The base 91 is bonded and fixed over the entire circumference of the flange-side end surface 2d of the outer ring 2 on the wheel mounting flange 3c side. And a protrusion 92 that forms a labyrinth gap S between the tip and the flange side surface 3f. The protrusion 92 has a low density protrusion 92b in which ciliary protrusions are roughly formed below the axis 01, and a high density in which cilia protrusions are densely formed above the axis 01. It consists of a protrusion 92a.

  As the weir member 9, for example, one surface of a hook-and-loop fastener (sold under the trade name of Velcro (registered trademark)) is used, and the shape of the protrusion 92 is a loop shape in addition to the linear shape shown in FIG. It may be a hook or the like.

  FIG. 3 is a perspective view of the weir member 9 of the wheel bearing device 1 according to the embodiment of the present invention. More specifically, the protrusion 92 of the dam member 9 is formed with a low density protrusion 92b below the axis 01 and having a ratio of 1/3 to the circumference, which is opposite to the low density protrusion 92b. The high-density protrusions 92a are formed so that the ratio to the circumference is approximately 2/3.

  The wheel bearing device 1 is configured such that when running on rain, muddy water containing rain water or a snow melting agent (hereinafter collectively referred to as “foreign matter”) is provided between the flange side surface 3f and the flange side end surface 2d. Try to penetrate inside.

  However, since the wheel bearing device 1 includes the dam member 9, the high-density protrusion 92a provided on the upper side of the bearing serves as a dam, and reduces the approach of foreign matter to the sliding contact surface of the axial lip 72d. In addition, since the low density protrusion 92b is provided on the lower side of the bearing, even if foreign matter enters between the axial lip 72d and the weir member 9, it can be discharged to the outside through the gap between the roughly formed protrusions. Furthermore, since the labyrinth gap S is formed, the approach of foreign matter to the sliding contact surface of the axial lip 72d can be suppressed.

  As described above, according to the wheel bearing device 1 according to the present embodiment, the dam member 9 includes the high-density protrusion 92a on the upper side of the bearing so as to face the flange side surface 3f. The approach of foreign matter to the sliding contact surface can be greatly reduced, and the sealing performance of the seal member 7 can be improved. Furthermore, since the weir member 9 includes the low-density protrusion 92b on the lower side of the bearing, foreign matter that has entered between the axial lip 72d and the weir member 72g is discharged to the outside from the gap between the roughly formed protrusions. And the sealing performance of the sealing member 7 can be improved.

  In the above embodiment, the sealing member 7 is increased in strength by the reinforcing metal core 71 to improve the sealing performance. However, the present invention is not limited thereto. For example, the sealing member has a small shape and requires a high strength. If not, the present invention may be applied to a configuration in which the core bar 71 is not provided.

  In the wheel bearing device 1 of the above embodiment, the weir member 9 is provided over the entire circumference of the flange-side end surface 2d. However, the invention is not limited thereto. For example, when the environment in which the vehicle is used is not a bad environment May be determined only by the configuration or environment of the vehicle to which the wheel bearing device is applied.

  Further, in the wheel bearing device 1 of the above-described embodiment, the protrusion 92 of the dam member 9 is formed with the low density protrusions 92b below the axis 01 and having a ratio to the circumference of approximately 1/3. The high-density protrusions 92a are formed so that the ratio to the circumference opposite to the density protrusions 92b is approximately 2/3. However, the present invention is not limited to this. For example, the vehicle often travels on rough roads. When intrusion of foreign matter is assumed from the installation surface side, it may be determined depending on the configuration or environment of the vehicle to which the wheel bearing device is applied, such as forming the high-density protrusion 92a over the entire circumference.

  In the wheel bearing device 1 of the above embodiment, the protrusion 92 of the weir member 9 forms the labyrinth gap S between the tip and the flange side surface 3f. However, the present invention is not limited thereto. However, it may be applied to a configuration that slides with a small contact pressure, that is, light contact with respect to the flange side surface 3f.

1: Wheel bearing device, 2: outer ring (outer ring member), 2d: flange side end surface, 3: inner shaft (inner ring member), 3c: wheel mounting flange (flange), 3f: flange side surface, 4: inner ring (inner ring) Member), 5: ball, 6: bearing internal space, 7, 8: seal member, 71: cored bar, 71a: cylindrical part, 71b: disc part, 72: seal (seal member), 72a: fitting part, 72b: seal base, 72c: lip, 72d: axial lip (lip), 72e, 72f: radial lip (lip), 9: weir member, 91: base, 92: protrusion, S: labyrinth gap, 92a: high Density protrusion, 92b: low density protrusion

Claims (4)

An outer ring member that is non-rotatably attached to the vehicle body side, and an inner ring member that is supported by the outer ring member so as to be rotatable around a shaft center via a rolling element. A flange is formed so as to protrude outward in the direction to attach a wheel, and is fitted to an inner peripheral surface end of the outer ring member on the flange side, so that the bearing inner portion between the outer ring member and the inner ring member In the wheel bearing device having a seal member that seals the space, the seal member having an annular lip that is made of an elastic member and continuously contacts the side surface of the flange.
A flange side end surface that is an end surface on the flange side of the outer ring member is provided with a synthetic resin weir member disposed to face the side surface of the flange,
The weir member has a base bonded to the flange-side end surface, and a plurality of protrusions protruding in a ciliary shape from the base, and the tip of the protrusion and the side surface of the flange are light contact or labyrinth gaps A bearing device for a wheel, characterized in that   The wheel bearing device according to claim 1, wherein the dam member is formed over the entire circumference of the flange-side end surface.   The wheel bearing device according to claim 1, wherein the protrusions are densely formed.   The wheel bearing device according to any one of claims 1 to 3, wherein the protrusion is formed so that a lower part of the protrusion is rougher than an upper part of the shaft.

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